1. Field of the Invention
The present invention relates generally to low glass transition temperature (low “Tg”) polyimide adhesives having aramid type fibers incorporated therein. More specifically, the polyimide compositions of the present invention have advantageous coefficient of thermal expansion (“CTE”) properties, thereby making the compositions particularly suitable and useful for metal bonding in electronics type applications or the like.
2. Discussion of Related Art
U.S. Pat. No. 6,743,273 to Chung et al. is directed to micro fibers having a diameter of 200 nanometers or less, useful as a filtering media, or useful as a filtering layer when deposited onto a cellulose substrate.
US Patent Application No. 2003-0045606 to Kusaka et al. teaches aramid resins having an average particle size of about 10 to 2000 microns. The aramid resins are used in combination with a binder (e.g., a phenol resin, an epoxy or a polyimide) to create a brake pad, brake drum, clutch plate or other friction intensive substrate.